Therapeutic human papillomavirus vaccines in head and neck cancer: A systematic review of current clinical trials

J. Ertl H. Preclinical Immunogenicity and Efficacy Studies for Therapeutic Vaccines for Human Papillomavirus-Type-16-Associated Cancer

The objective of this study was to conduct preclinical immunogenicity and efficacy studies with several therapeutic vaccines for human papillomavirus (HPV)-16-associated cancers expressing the early antigens E5, E6, and E7 with or without E2. The viral oncoproteins were either expressed by themselves as fusion proteins or the fusion proteins were inserted genetically into herpes simplex virus (HSV)-1 glycoprotein D (gD) which, upon binding to the herpes virus entry mediator (HVEM), inhibits an early T cell checkpoint mediated by the B and T cell mediator (BTLA). This, in turn, lowers the threshold for T cell activation and augments and broadens CD8+ T cell responses to the antigens. The fusion antigens were expressed by chimpanzee adenovirus (AdC) vectors. Expression of the HPV antigens within gD was essential for vaccine immunogenicity and efficacy against challenge with TC-1 cells, which express E7 and E6 of HPV-16 but neither E5 nor E2. Unexpectedly, inclusion of E2 increased both CD8+ T cell responses to the other oncoproteins of HPV-16 and the effectiveness of the vaccines to cause the regression of sizable TC-1 tumors.

Head and Neck Squamous Cell Carcinoma Vaccine: Current Landscape and Perspectives

The treatment of unresectable or metastatic Head and Neck Squamous Cell Carcinoma (HNSCC) has traditionally relied on chemotherapy or radiotherapy, yielding suboptimal outcomes. The introduction of immunotherapy has significantly improved HNSCC treatment, even if the long-term results cannot be defined as satisfactory. Its mechanism of action aims to counteract the blockade of tumor immune escape. This result can also be obtained by stimulating the immune system with vaccines. This review scope is to comprehensively gather existing evidence and summarize ongoing clinical trials focused on therapeutic vaccines for HNSCC treatment. The current landscape reveals numerous promising drugs in the early stages of experimentation, along with a multitude of trials that have been suspended or abandoned for years. Nonetheless, there are encouraging results and ongoing experiments that instill hope for potential paradigm shifts in HNSCC therapy.

Influence of pathogens on host genome and epigenome in development of head and neck cancer

BACKGROUND

Head and neck cancer (HNSCC) is a heterogeneous group of cancers, affecting multiple regions such as oral cavity, pharynx, larynx, and nasal region, each showing a distinct molecular profile. HNSCC accounts for more than 6 million cases worldwide, soaring mainly in the developing countries.

RECENT FINDINGS

The aetiology of HNSCC is complex and multifactorial, involving both genetic and environmental factors. The critical role of microbiome, which includes bacteria, viruses, and fungi, is under spotlight due to the recent reports on their contribution in the development and progression of HNSCC. This review focuses on the effect of opportunistic pathogens on the host genome and epigenome, which contributes to the disease progression. Drawing parallels from the host-pathogen interactions observed in other tumour types arising from the epithelial tissue such as colorectal cancer, the review also calls attention to the potential explorations of the role of pathogens in HNSCC biology and discusses the clinical implications of microbiome research in detection and treatment of HNSCC.

CONCLUSION

Our understanding of the genomic effects of the microbes on the disease progression and the mechanistic insights of the host-pathogen interaction will pave way to novel treatment and preventive approaches in HNSCC.

Therapeutic Vaccination in Head and Neck Squamous Cell Carcinoma—A Review

Therapeutic vaccination is one of the most effective immunotherapeutic approaches, second only to immune checkpoint inhibitors (ICIs), which have already been approved for clinical use. Head and neck squamous cell carcinomas (HNSCCs) are heterogenous epithelial tumors of the upper aerodigestive tract, and a significant proportion of these tumors tend to exhibit unfavorable therapeutic responses to the existing treatment options. Comprehending the immunopathology of these tumors and choosing an appropriate immunotherapeutic maneuver seems to be a promising avenue for solving this problem. The current review provides a detailed overview of the strategies, targets, and candidates for therapeutic vaccination in HNSCC. The classical principle of inducing a potent, antigen-specific, cell-mediated cytotoxicity targeting a specific tumor antigen seems to be the most effective mechanism of therapeutic vaccination, particularly against the human papilloma virus positive subset of HNSCC. However, approaches such as countering the immunosuppressive tumor microenvironment of HNSCC and immune co-stimulatory mechanisms have also been explored recently, with encouraging results.

Nanomaterials for mRNA ‐based Therapeutics: Challenges and Opportunities

Messenger RNA (mRNA) holds great potential in developing immunotherapy, protein replacement, and genome editing. In general, mRNA does not have the risk of being incorporated into the host genome and does not need to enter the nucleus for transfection, and it can be expressed even in nondividing cells. Therefore, mRNA-based therapeutics provide a promising strategy for clinical treatment. However, the efficient and safe delivery of mRNA remains a crucial constraint for the clinical application of mRNA therapeutics. Although the stability and tolerability of mRNA can be enhanced by directly retouching the mRNA structure, there is still an urgent need to improve the delivery of mRNA. Recently, significant progress has been made in nanobiotechnology, providing tools for developing mRNA nanocarriers. Nano-drug delivery system is directly used for loading, protecting, and releasing mRNA in the biological microenvironment and can be used to stimulate the translation of mRNA to develop effective intervention strategies. In the present review, we summarized the concept of emerging nanomaterials for mRNA delivery and the latest progress in enhancing the function of mRNA, primarily focusing on the role of exosomes in mRNA delivery. Moreover, we outlined its clinical applications so far. Finally, the key obstacles of mRNA nanocarriers are emphasized, and promising strategies to overcome these obstacles are proposed. Collectively, nano-design materials exert functions for specific mRNA applications, provide new perception for next-generation nanomaterials, and thus revolution of mRNA technology.

Therapeutic Vaccination for HPV-Mediated Cancers

Purpose of Review

The goal of this narrative review is to educate clinicians regarding the foundational concepts, efficacy, and future directions of therapeutic vaccines for human papillomavirus (HPV)-mediated cancers.

Recent Findings

Therapeutic HPV vaccines deliver tumor antigens to stimulate an immune response to eliminate tumor cells. Vaccine antigen delivery platforms are diverse and include DNA, RNA, peptides, proteins, viral vectors, microbial vectors, and antigen-presenting cells. Randomized, controlled trials have demonstrated that therapeutic HPV vaccines are efficacious in patients with cervical intraepithelial neoplasia. In patients with HPV-mediated malignancies, evidence of efficacy is limited. However, numerous ongoing studies evaluating updated therapeutic HPV vaccines in combination with immune checkpoint inhibition and other therapies exhibit significant promise.

Summary

Therapeutic vaccines for HPV-mediated malignancies retain a strong biological rationale, despite their limited efficacy to date. Investigators anticipate they will be most effectively used in combination with other regimens, such as immune checkpoint inhibition.

Oral infections in oral cancer survivors: A mini-review

The oral cancer survivors are a group of special individuals whose disease affect anatomical structures with a key role in identity and communication and a fundamental role in basic human functions such as speaking, eating, swallowing and breathing. Thus, quality of life of these individuals can be impaired by the consequences of disease and treatments, in particular surgery and radiotherapy. Among others, infectious conditions of any nature, bacterial, viral, fungal, are a frequent finding among oral cancer survivors. In fact, the peculiar systemic and local conditions of these subjects are known to significantly modify the microbiota, which, besides facilitating opportunistic infections, can affect the cancer microenvironment, as well as alter the effects of the anti-cancer therapies. Similarly, mouth infections can also affect the prognosis of oral cancer survivors. Among the opportunistic infections, fungal are the most common infections affecting these subjects, since neutropenia resulting from cancer, as well as chemotherapy and/or radiotherapy treatments, promote the shift from the carrier state of Candida species, to pathogen state. Treatment of oral candidiasis can be difficult in oral cancer survivors, and good evidence supports clotrimazole as the most effective for prevention, and fluconazole as the one with the best risk-benefit profile. Probiotics, although promising, need better evidence to be considered an effective treatment or preventive measure.

HPV Vaccination: An Underused Strategy for the Prevention of Cancer

Human papillomavirus (HPV) vaccination prevents cervical, head and neck, and anogenital cancers. However, global HPV vaccine coverage falls short of global targets and has seen unexpected and dramatic declines in some countries. This paper synthesizes the impact of HPV on the global burden of cancer and the potential benefit of HPV vaccination. Approximately 5% of the world’s cancers are specifically attributed to HPV. While the greatest global burden of HPV is cervical cancers in low- and middle-income countries, HPV-associated head and neck cancers are increasing in high-income countries and have surpassed cervical cancer as the primary HPV-associated cancer in some countries. Therefore, it is also critical to improve gender-neutral HPV vaccination. Understanding the modifiable drivers of vaccine acceptance and uptake is important for increasing HPV vaccination. The Behavioural and Social Drivers of Vaccination framework is broadly applied to identify key factors associated with HPV vaccination including domains concerning practical issues, motivation, social processes, and thinking and feeling. Among the behavioural strategies available to reduce the incidence and mortality of cancer, increasing HPV vaccination stands out as having unrealized potential to prevent disease, financial cost, and psychological distress. An understanding of the shifting burden of HPV and the factors associated with vaccination can be leveraged to regularly measure these factors, develop interventions to promote vaccine uptake, and improve global HPV vaccine coverage. Future research in diverse contexts is necessary to investigate the barriers and facilitators of global HPV vaccination.

HPV Vaccination after Primary Treatment of HPV-Related Disease across Different Organ Sites: A Multidisciplinary Comprehensive Review and Meta-Analysis

Objective: To assess evidence on the efficacy of adjuvant human papillomavirus (HPV) vaccination in patients treated for HPV-related disease across different susceptible organ sites. Methods: A systematic review was conducted to identify studies addressing the efficacy of adjuvant HPV vaccination on reducing the risk of recurrence of HPV-related preinvasive diseases. Results were reported as mean differences or pooled odds ratios (OR) with 95% confidence intervals (95% CI). Results: Sixteen studies were identified for the final analysis. Overall, 21,472 patients with cervical dysplasia were included: 4132 (19.2%) received the peri-operative HPV vaccine, while 17,340 (80.8%) underwent surgical treatment alone. The recurrences of CIN 1+ (OR 0.45, 95% CI 0.27 to 0.73; p = 0.001), CIN 2+ (OR 0.33, 95% CI 0.20 to 0.52; p < 0.0001), and CIN 3 (OR 0.28, 95% CI 0.13 to 0.59; p = 0.0009) were lower in the vaccinated than in unvaccinated group. Similarly, adjuvant vaccination reduced the risk of developing anal intraepithelial neoplasia (p = 0.005) and recurrent respiratory papillomatosis (p = 0.004). No differences in anogenital warts and vulvar intraepithelial neoplasia recurrence rate were observed comparing vaccinated and unvaccinated individuals. Conclusions: Adjuvant HPV vaccination is associated with a reduced risk of CIN recurrence, although there are limited data regarding its role in other HPV-related diseases. Further research is warranted to shed more light on the role of HPV vaccination as adjuvant therapy after primary treatment.

Head and Neck Squamous Cell Carcinoma: Risk Factors, Molecular Alterations, Immunology and Peptide Vaccines

Head and neck squamous cell carcinoma (HNSCC) arises from the epithelial lining of the oral cavity, hypopharynx, oropharynx, and larynx. There are several potential risk factors that cause the generation of HNSCC, including cigarette smoking, alcohol consumption, betel quid chewing, inadequate nutrition, poor oral hygiene, HPV and Epstein–Barr virus, and Candida albicans infections. HNSCC has causative links to both environmental factors and genetic mutations, with the latter playing a more critical role in cancer progression. These molecular changes to epithelial cells include the inactivation of cancer suppressor genes and proto-oncogenes overexpression, resulting in tumour cell proliferation and distant metastasis. HNSCC patients have impaired dendritic cell (DC) and natural killer (NK) cell functions, increased production of higher immune-suppressive molecules, loss of regulatory T cells and co-stimulatory molecules and major histocompatibility complex (MHC) class Ι molecules, lower number of lymphocyte subsets, and a poor response to antigen-presenting cells. At present, the standard treatment modalities for HNSCC patients include surgery, chemotherapy and radiotherapy, and combinatorial therapy. Despite advances in the development of novel treatment modalities over the last few decades, survival rates of HNSCC patients have not increased. To establish effective immunotherapies, a greater understanding of interactions between the immune system and HNSCC is required, and there is a particular need to develop novel therapeutic options. A therapeutic cancer vaccine has been proposed as a promising method to improve outcome by inducing a powerful adaptive immune response that leads to cancer cell elimination. Compared with other vaccines, peptide cancer vaccines are more robust and specific. In the past few years, there have been remarkable achievements in peptide-based vaccines for HNSCC patients. Here, we summarize the latest molecular alterations in HNSCC, explore the immune response to HNSCC, and discuss the latest developments in peptide-based cancer vaccine strategies. This review highlights areas for valuable future research focusing on peptide-based cancer vaccines.

Vaccine-Based Immunotherapy for Head and Neck Cancers

Simple Summary

Therapeutic vaccines are given to patients with cancer, as opposed to prophylactic vaccines given to a healthy population. The challenge for therapeutic oncological vaccines is to stimulate an immune T cell response against endogenous (or derived) antigens that is sufficiently potent to induce cytotoxic activity and broad enough to take tumor heterogeneity into account. The purpose of this article is to provide an updated review of the prophylactic and therapeutic vaccines that target viral or non-viral antigens, particularly in head and neck cancers.

Abstract

In 2019, the FDA approved pembrolizumab, a monoclonal antibody targeting PD-1, for the first-line treatment of recurrent or metastatic head and neck cancers, despite only a limited number of patients benefiting from the treatment. Promising effects of therapeutic vaccination led the FDA to approve the use of the first therapeutic vaccine in prostate cancer in 2010. Research in the field of therapeutic vaccination, including possible synergistic effects with anti-PD(L)1 treatments, is evolving each year, and many vaccines are in pre-clinical and clinical studies. The aim of this review article is to discuss vaccines as a new therapeutic strategy, particularly in the field of head and neck cancers. Different vaccination technologies are discussed, as well as the results of the first clinical trials in HPV-positive, HPV-negative, and EBV-induced head and neck cancers.

Nurse-led oral and maxillofacial oncology clinics: a review

The "nurse-led" oral and maxillofacial (OMFS) head and neck (H&N) clinic has been introduced and developed over the last decade, and we are now close to a point that this endeavour can potentially be implemented nationwide. This paper is a systematic review of the proposed OMFS H&N nurse-led clinic model. Literature on the topic is limited: only eight eligible papers were identified and reviewed. These were appraised focusing on four domains: requirement/necessity, true cost, patient safety and outcomes, and education and training. Most of the advantages/proposed benefits of these clinics have previously been discussed. This current review has revealed that the available published evidence on the concept of OMFS H&N nurse-led clinics demonstrates that they might not be necessary. The alleged cost savings have not been described in detail and might not be as significant as expected, more intense collaboration is required to establish watertight quality assurance processes concerning patient safety, and the clinics might have an impact on the education and training of OMFS trainees. The nurse-led clinic concept is interesting and exciting, but more discussion and planning is needed prior to it being launched nationwide.

Serum Anti-HPV Antibody Titer as a Marker of Vaccine Effectiveness in Males with Genital Infection

Introduction: Persistent human papillomavirus (HPV) semen infection is increasingly associated with male infertility. Adjuvant HPV vaccination is suggested to reduce the time to clearance and the disease relapse in males with persistent HPV semen infection. However, only a sub-population of patients show a clinical benefit from adjuvant vaccination. Here, we aimed to address the effectiveness rate of HPV adjuvant vaccination in males with genital tract infection and the possible prognostic markers of healing. Methods: Clinical records from 379 patients with persistent seminal HPV detection, all receiving HPV adjuvant vaccination, were considered. Clinical data, including genital HPV-DNA assessment by INNO-LiPA genotyping, semen HPV-DNA analysis by FISH analysis and serum antibody titer, were collected at basal (T0) and after 6 months (T1) since the vaccination cycle ended. Results: Clearance of genital HPV-DNA was recorded in 326 (86%) patients. Serum HPV-antibody titer at T1 was the most important prognostic factor associated with HPV-DNA clearance. A serum antibody titer equal to or greater than the threshold value 1:125, obtained by ROC curve analysis, was prognostic of healing. Conclusions: Anti-HPV antibody represents a suitable marker of adequate immune response to HPV vaccination in patients with genital infection.

Considerations in Human Papillomavirus-Associated Oropharyngeal Cancer Screening: A Review

Importance

The incidence of human papillomavirus (HPV)-positive oropharyngeal cancer (OPC) is anticipated to rise over the next few decades until the effects of prophylactic vaccination are realized, which highlights the potential importance of secondary prevention. The objective of this review is to evaluate the evidence associated with screening for HPV-positive OPC.

Observations

Evaluation of a potential clinical preventive screening service requires characterization of the disease burden, the at-risk target screening population, screening tests, treatment, and screening benefits and harms. The lifetime risk of OPC is 0.7% for men and 0.2% for women and is expected to increase. The disease burden of HPV-positive OPC is substantial; most patients undergo morbid multimodality treatment and incur high costs in the process. Middle-aged and older adult men with elevated number of lifetime vaginal or oral sex partners are at highest risk. Patients may benefit from early detection of the disease-the 4-year overall survival of patients with stage I HPV-positive OPC is 87%, a considerable portion of whom are eligible for less morbid single-modality therapy. However, available screening tests are insufficiently sensitive and specific considering the current HPV-positive OPC incidence rates in the most at-risk patients. Further, the benefits and harms of screening for HPV-positive OPC are unknown.

Conclusions and Relevance

The current and projected future population-level burden of HPV-positive OPC supports further exploration of secondary preventive interventions. However, screening for HPV-positive OPC is not currently justified. Advances in biomarker discovery and improved characterization of (1) a highly at-risk, target screening population and (2) the benefits and harms of screening will be necessary. Large-scale clinical trials and rigorous evaluation of how to best implement this service into clinical practice will also be needed.

Could the human papillomavirus vaccine prevent recurrence of ano-genital warts?: a systematic review and meta-analysis

Human papillomavirus (HPV) is the most prevalent sexually transmitted infection worldwide and ano-genital warts (AGWs) are highly infectious. This virus is transmitted through sexual, anal, or oral contact as well as skin-to-skin contacts. Treatment for this condition has significant morbidity and it can be frustrating in certain cases. The HPV vaccination has been demonstrated as a promising strategy of secondary prevention in HPV-related diseases such as head and neck cancers, cervical diseases, and recurrent respiratory papillomatosis. Regarding AGWs, it is unclear whether vaccination can provide analogous clinical benefit. The aim of this work is to systematically review the literature regarding HPV vaccination for secondary disease prevention after treatment of AGWs. From October to December 2018, a systematic search for clinical trials was conducted in five databases: PubMed, MEDLINE, EMBASE, Cochrane, and clinicaltrials.gov using a combination of the following descriptors: 'gardasil' OR 'cervarix' OR 'nine-valent' OR '9-valent' OR 'vaccine' AND 'recurrence' OR 'relapse' AND 'hpv' OR 'papillomavirus' AND 'warts' OR 'condyloma.' Data were synthetized and entered in the Review Manager software (RevMan 5.3.5) to perform the meta-analysis. The search yielded 824 potentially relevant studies. Two studies fulfilled the eligibility criteria involving 656 participants. The meta-analysis estimated the rate of recurrence of AGWs was similar between the vaccine group and the control group. The overall effect estimate was 1.02 (0.75-1.38). This is the first meta-analysis exploring the effect of HPV vaccine in preventing the relapse of AGWs. These results suggest that HPV vaccination does not provide secondary benefit in patients with previous AGWs. However, these results cannot be generalized due to the scarce number of RCTs currently available in the literature. The outcomes from future randomized controlled trials (RCTs) are warranted to further clarify the precise effect of the vaccine.

DNMT1 Enhances the Radiosensitivity of HPV-Positive Head and Neck Squamous Cell Carcinomas via Downregulating SMG1

Introduction

Head and neck squamous cell carcinoma (HNSCC), which rank the 7th malignant tumors worldwide, is closely related to methylation and HPV infection. Ionizing radiation therapy is the main strategy for HNSCC patients in advanced stage. Previously, HPV-positive HNSCC predict better prognosis than HPV-negative HNSCCs under radiotherapy, however its molecular mechanism is unresolved. SMG1 serves as a potential tumor suppressor in various cancers, including HNSCC.

Methods

The mRNAs and proteins expression of HPV E6/E7, p16, p53, DNMT1, SMG1 were detected after different treatments by qPCR and Western blot. The clone formation ability was measured in radiation dose after different treatments.

Results

In our study, the expression of HPV16 E6, DNA Methyltransferase 1(DNMT1) and SMG1 in head and neck carcinomas cell lines was detected by RT-qPCR and Western blot. Forced E6 level in HPV-negative cells by overexpression plasmid promoted the expression of DNMT1, which resulted in decreased SMG1 expression. Silenced SMG1 in HPV-negative HNSCC cells elicited increased radiation sensitivity, suggesting that SMG1 may be an effective switch to regulate the effect of radiotherapy in HNSCC.

Conclusion

Our study indicated that DNMT1 enhances the radiosensitivity of HPV-positive head and neck squamous cell carcinomas via downregulating SMG1.

Therapeutic Vaccines Against Human Papilloma Viruses: Achievements and Prospects

Human papillomaviruses of high carcinogenic risk (HR HPVs) are major etiological agents of malignant diseases of the cervix, vulva, penis, anal canal, larynx, head, and neck. Prophylactic vaccination against HPV, which mainly covers girls and women under 25, does not prevent vertical and horizontal HPV transmission in infants and children and does not have a therapeutic effect. As a result, a significant proportion of the population is not protected from the HPV infection and development of HPV-associated neoplastic transformation and cancer, which indicates the need for development and introduction of therapeutic HPV vaccines. Unlike prophylactic vaccines aimed at the formation of virus-neutralizing antibodies, therapeutic vaccines elicit cellular immune response leading to the elimination of infected and malignant cells expressing viral proteins. The ideal targets for vaccine immunotherapy are highly conserved HR HPV oncoproteins E6 and E7 expressed in precancerous and tumor tissues. Here, we describe expression of these proteins during different stages of HPV infection, their antigenic and immunogenic properties, and T-cell epitopes, the response to which correlates with natural regression of HPV-induced neoplastic changes. The review describes patterns of E6 and E7 oncoproteins presentation to the immune system as components of candidate vaccines along with the results of the most promising preclinical trials and animal models used in these trials. Special attention is paid to vaccine candidates which have shown efficacy in clinical trials in patients with HPV-associated neoplastic changes.

Targeting the Immune Microenvironment in the Treatment of Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) is a highly aggressive solid tumor, with a 5-year mortality rate of ~50%. The development of immunotherapies has improved the survival of patients with HNSCC, but, the long-term prognosis of patients with recurrent or metastatic HNSCC remains poor. HNSCC is characterized by intratumoral infiltration of regulatory T cells, dysfunctional natural killer cells, an elevated Treg/CD8+ T cell ratio, and increased programmed cell death ligand 1 protein on tumor cells. This leads to an immunocompromised niche in favor of the proliferation and treatment resistance of cancer cells. To achieve an improved treatment response, several potential combination strategies, such as increasing the neoantigens for antigen presentation and therapeutic agents targeting components of the tumor microenvironment, have been explored and have shown promising results in preclinical studies. In addition, large-scale bioinformatic studies have also identified possible predictive biomarkers of HNSCC. As immunotherapy has shown survival benefits in recent HNSCC clinical trials, a comprehensive investigation of immune cells and immune-related factors/cytokines and the immune profiling of tumor cells during the development of HNSCC may provide more insights into the complex immune microenvironment and thus, facilitate the development of novel immunotherapeutic agents.

Heterogeneity of the Head and Neck Squamous Cell Carcinoma Immune Landscape and Its Impact on Immunotherapy

Head and neck squamous cell carcinomas (HNSCCs) are highly aggressive, multi-factorial tumors in the upper aerodigestive tract affecting more than half a million patients worldwide each year. Alcohol, tobacco, and human papillomavirus (HPV) infection are well known causative factors for HNSCCs. Current treatment options for HNSCCs are surgery, radiotherapy, chemotherapy, or combinatorial remedies. Over the past decade, despite the marked improvement in clinical outcome of many tumor types, the overall 5-year survival rate of HNSCCs remained ∼40–50% largely due to poor availability of effective therapeutic options for HNSCC patients with recurrent disease. Therefore, there is an urgent and unmet need for the identification of specific molecular signatures that better predict the clinical outcomes and markers that serve as better therapeutic targets. With recent technological advances in genomic and epigenetic analyses, our knowledge of HNSCC molecular characteristics and classification has been greatly enriched. Clinical and genomic meta-analysis of multicohort HNSCC gene expression profile has clearly demonstrated that HPV⁺ and HPV^- HNSCCs are not only derived from tissues of different anatomical regions, but also present with different mutation profiles, molecular characteristics, immune landscapes, and clinical prognosis. Here, we briefly review our current understanding of the biology, molecular profile, and immunological landscape of the HPV⁺ and HPV^- HNSCCs with an emphasis on the diversity and heterogeneity of HNSCC clinicopathology and therapeutic responses. After a review of recent advances and specific challenges for effective immunotherapy of HNSCCs, we then conclude with a discussion on the need to further enhance our understanding of the unique characteristics of HNSCC heterogeneity and the plasticity of immune landscape. Increased knowledge regarding the immunological characteristics of HPV⁺ and HPV^- HNSCCs would improve therapeutic targeting and immunotherapy strategies for different subtypes of HNSCCs.